--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/third_party/luajit/src/lib_debug.c	Thu Jan 22 20:10:30 2026 -0800
@@ -0,0 +1,406 @@
+/*
+** Debug library.
+** Copyright (C) 2005-2023 Mike Pall. See Copyright Notice in luajit.h
+**
+** Major portions taken verbatim or adapted from the Lua interpreter.
+** Copyright (C) 1994-2008 Lua.org, PUC-Rio. See Copyright Notice in lua.h
+*/
+
+#define lib_debug_c
+#define LUA_LIB
+
+#include "lua.h"
+#include "lauxlib.h"
+#include "lualib.h"
+
+#include "lj_obj.h"
+#include "lj_gc.h"
+#include "lj_err.h"
+#include "lj_debug.h"
+#include "lj_lib.h"
+
+/* ------------------------------------------------------------------------ */
+
+#define LJLIB_MODULE_debug
+
+LJLIB_CF(debug_getregistry)
+{
+  copyTV(L, L->top++, registry(L));
+  return 1;
+}
+
+LJLIB_CF(debug_getmetatable)	LJLIB_REC(.)
+{
+  lj_lib_checkany(L, 1);
+  if (!lua_getmetatable(L, 1)) {
+    setnilV(L->top-1);
+  }
+  return 1;
+}
+
+LJLIB_CF(debug_setmetatable)
+{
+  lj_lib_checktabornil(L, 2);
+  L->top = L->base+2;
+  lua_setmetatable(L, 1);
+#if !LJ_52
+  setboolV(L->top-1, 1);
+#endif
+  return 1;
+}
+
+LJLIB_CF(debug_getfenv)
+{
+  lj_lib_checkany(L, 1);
+  lua_getfenv(L, 1);
+  return 1;
+}
+
+LJLIB_CF(debug_setfenv)
+{
+  lj_lib_checktab(L, 2);
+  L->top = L->base+2;
+  if (!lua_setfenv(L, 1))
+    lj_err_caller(L, LJ_ERR_SETFENV);
+  return 1;
+}
+
+/* ------------------------------------------------------------------------ */
+
+static void settabss(lua_State *L, const char *i, const char *v)
+{
+  lua_pushstring(L, v);
+  lua_setfield(L, -2, i);
+}
+
+static void settabsi(lua_State *L, const char *i, int v)
+{
+  lua_pushinteger(L, v);
+  lua_setfield(L, -2, i);
+}
+
+static void settabsb(lua_State *L, const char *i, int v)
+{
+  lua_pushboolean(L, v);
+  lua_setfield(L, -2, i);
+}
+
+static lua_State *getthread(lua_State *L, int *arg)
+{
+  if (L->base < L->top && tvisthread(L->base)) {
+    *arg = 1;
+    return threadV(L->base);
+  } else {
+    *arg = 0;
+    return L;
+  }
+}
+
+static void treatstackoption(lua_State *L, lua_State *L1, const char *fname)
+{
+  if (L == L1) {
+    lua_pushvalue(L, -2);
+    lua_remove(L, -3);
+  }
+  else
+    lua_xmove(L1, L, 1);
+  lua_setfield(L, -2, fname);
+}
+
+LJLIB_CF(debug_getinfo)
+{
+  lj_Debug ar;
+  int arg, opt_f = 0, opt_L = 0;
+  lua_State *L1 = getthread(L, &arg);
+  const char *options = luaL_optstring(L, arg+2, "flnSu");
+  if (lua_isnumber(L, arg+1)) {
+    if (!lua_getstack(L1, (int)lua_tointeger(L, arg+1), (lua_Debug *)&ar)) {
+      setnilV(L->top-1);
+      return 1;
+    }
+  } else if (L->base+arg < L->top && tvisfunc(L->base+arg)) {
+    options = lua_pushfstring(L, ">%s", options);
+    setfuncV(L1, L1->top++, funcV(L->base+arg));
+  } else {
+    lj_err_arg(L, arg+1, LJ_ERR_NOFUNCL);
+  }
+  if (!lj_debug_getinfo(L1, options, &ar, 1))
+    lj_err_arg(L, arg+2, LJ_ERR_INVOPT);
+  lua_createtable(L, 0, 16);  /* Create result table. */
+  for (; *options; options++) {
+    switch (*options) {
+    case 'S':
+      settabss(L, "source", ar.source);
+      settabss(L, "short_src", ar.short_src);
+      settabsi(L, "linedefined", ar.linedefined);
+      settabsi(L, "lastlinedefined", ar.lastlinedefined);
+      settabss(L, "what", ar.what);
+      break;
+    case 'l':
+      settabsi(L, "currentline", ar.currentline);
+      break;
+    case 'u':
+      settabsi(L, "nups", ar.nups);
+      settabsi(L, "nparams", ar.nparams);
+      settabsb(L, "isvararg", ar.isvararg);
+      break;
+    case 'n':
+      settabss(L, "name", ar.name);
+      settabss(L, "namewhat", ar.namewhat);
+      break;
+    case 'f': opt_f = 1; break;
+    case 'L': opt_L = 1; break;
+    default: break;
+    }
+  }
+  if (opt_L) treatstackoption(L, L1, "activelines");
+  if (opt_f) treatstackoption(L, L1, "func");
+  return 1;  /* Return result table. */
+}
+
+LJLIB_CF(debug_getlocal)
+{
+  int arg;
+  lua_State *L1 = getthread(L, &arg);
+  lua_Debug ar;
+  const char *name;
+  int slot = lj_lib_checkint(L, arg+2);
+  if (tvisfunc(L->base+arg)) {
+    L->top = L->base+arg+1;
+    lua_pushstring(L, lua_getlocal(L, NULL, slot));
+    return 1;
+  }
+  if (!lua_getstack(L1, lj_lib_checkint(L, arg+1), &ar))
+    lj_err_arg(L, arg+1, LJ_ERR_LVLRNG);
+  name = lua_getlocal(L1, &ar, slot);
+  if (name) {
+    lua_xmove(L1, L, 1);
+    lua_pushstring(L, name);
+    lua_pushvalue(L, -2);
+    return 2;
+  } else {
+    setnilV(L->top-1);
+    return 1;
+  }
+}
+
+LJLIB_CF(debug_setlocal)
+{
+  int arg;
+  lua_State *L1 = getthread(L, &arg);
+  lua_Debug ar;
+  TValue *tv;
+  if (!lua_getstack(L1, lj_lib_checkint(L, arg+1), &ar))
+    lj_err_arg(L, arg+1, LJ_ERR_LVLRNG);
+  tv = lj_lib_checkany(L, arg+3);
+  copyTV(L1, L1->top++, tv);
+  lua_pushstring(L, lua_setlocal(L1, &ar, lj_lib_checkint(L, arg+2)));
+  return 1;
+}
+
+static int debug_getupvalue(lua_State *L, int get)
+{
+  int32_t n = lj_lib_checkint(L, 2);
+  const char *name;
+  lj_lib_checkfunc(L, 1);
+  name = get ? lua_getupvalue(L, 1, n) : lua_setupvalue(L, 1, n);
+  if (name) {
+    lua_pushstring(L, name);
+    if (!get) return 1;
+    copyTV(L, L->top, L->top-2);
+    L->top++;
+    return 2;
+  }
+  return 0;
+}
+
+LJLIB_CF(debug_getupvalue)
+{
+  return debug_getupvalue(L, 1);
+}
+
+LJLIB_CF(debug_setupvalue)
+{
+  lj_lib_checkany(L, 3);
+  return debug_getupvalue(L, 0);
+}
+
+LJLIB_CF(debug_upvalueid)
+{
+  GCfunc *fn = lj_lib_checkfunc(L, 1);
+  int32_t n = lj_lib_checkint(L, 2) - 1;
+  if ((uint32_t)n >= fn->l.nupvalues)
+    lj_err_arg(L, 2, LJ_ERR_IDXRNG);
+  lua_pushlightuserdata(L, isluafunc(fn) ? (void *)gcref(fn->l.uvptr[n]) :
+					   (void *)&fn->c.upvalue[n]);
+  return 1;
+}
+
+LJLIB_CF(debug_upvaluejoin)
+{
+  GCfunc *fn[2];
+  GCRef *p[2];
+  int i;
+  for (i = 0; i < 2; i++) {
+    int32_t n;
+    fn[i] = lj_lib_checkfunc(L, 2*i+1);
+    if (!isluafunc(fn[i]))
+      lj_err_arg(L, 2*i+1, LJ_ERR_NOLFUNC);
+    n = lj_lib_checkint(L, 2*i+2) - 1;
+    if ((uint32_t)n >= fn[i]->l.nupvalues)
+      lj_err_arg(L, 2*i+2, LJ_ERR_IDXRNG);
+    p[i] = &fn[i]->l.uvptr[n];
+  }
+  setgcrefr(*p[0], *p[1]);
+  lj_gc_objbarrier(L, fn[0], gcref(*p[1]));
+  return 0;
+}
+
+#if LJ_52
+LJLIB_CF(debug_getuservalue)
+{
+  TValue *o = L->base;
+  if (o < L->top && tvisudata(o))
+    settabV(L, o, tabref(udataV(o)->env));
+  else
+    setnilV(o);
+  L->top = o+1;
+  return 1;
+}
+
+LJLIB_CF(debug_setuservalue)
+{
+  TValue *o = L->base;
+  if (!(o < L->top && tvisudata(o)))
+    lj_err_argt(L, 1, LUA_TUSERDATA);
+  if (!(o+1 < L->top && tvistab(o+1)))
+    lj_err_argt(L, 2, LUA_TTABLE);
+  L->top = o+2;
+  lua_setfenv(L, 1);
+  return 1;
+}
+#endif
+
+/* ------------------------------------------------------------------------ */
+
+#define KEY_HOOK	(U64x(80000000,00000000)|'h')
+
+static void hookf(lua_State *L, lua_Debug *ar)
+{
+  static const char *const hooknames[] =
+    {"call", "return", "line", "count", "tail return"};
+  (L->top++)->u64 = KEY_HOOK;
+  lua_rawget(L, LUA_REGISTRYINDEX);
+  if (lua_isfunction(L, -1)) {
+    lua_pushstring(L, hooknames[(int)ar->event]);
+    if (ar->currentline >= 0)
+      lua_pushinteger(L, ar->currentline);
+    else lua_pushnil(L);
+    lua_call(L, 2, 0);
+  }
+}
+
+static int makemask(const char *smask, int count)
+{
+  int mask = 0;
+  if (strchr(smask, 'c')) mask |= LUA_MASKCALL;
+  if (strchr(smask, 'r')) mask |= LUA_MASKRET;
+  if (strchr(smask, 'l')) mask |= LUA_MASKLINE;
+  if (count > 0) mask |= LUA_MASKCOUNT;
+  return mask;
+}
+
+static char *unmakemask(int mask, char *smask)
+{
+  int i = 0;
+  if (mask & LUA_MASKCALL) smask[i++] = 'c';
+  if (mask & LUA_MASKRET) smask[i++] = 'r';
+  if (mask & LUA_MASKLINE) smask[i++] = 'l';
+  smask[i] = '\0';
+  return smask;
+}
+
+LJLIB_CF(debug_sethook)
+{
+  int arg, mask, count;
+  lua_Hook func;
+  (void)getthread(L, &arg);
+  if (lua_isnoneornil(L, arg+1)) {
+    lua_settop(L, arg+1);
+    func = NULL; mask = 0; count = 0;  /* turn off hooks */
+  } else {
+    const char *smask = luaL_checkstring(L, arg+2);
+    luaL_checktype(L, arg+1, LUA_TFUNCTION);
+    count = luaL_optint(L, arg+3, 0);
+    func = hookf; mask = makemask(smask, count);
+  }
+  (L->top++)->u64 = KEY_HOOK;
+  lua_pushvalue(L, arg+1);
+  lua_rawset(L, LUA_REGISTRYINDEX);
+  lua_sethook(L, func, mask, count);
+  return 0;
+}
+
+LJLIB_CF(debug_gethook)
+{
+  char buff[5];
+  int mask = lua_gethookmask(L);
+  lua_Hook hook = lua_gethook(L);
+  if (hook != NULL && hook != hookf) {  /* external hook? */
+    lua_pushliteral(L, "external hook");
+  } else {
+    (L->top++)->u64 = KEY_HOOK;
+    lua_rawget(L, LUA_REGISTRYINDEX);   /* get hook */
+  }
+  lua_pushstring(L, unmakemask(mask, buff));
+  lua_pushinteger(L, lua_gethookcount(L));
+  return 3;
+}
+
+/* ------------------------------------------------------------------------ */
+
+LJLIB_CF(debug_debug)
+{
+  for (;;) {
+    char buffer[250];
+    fputs("lua_debug> ", stderr);
+    if (fgets(buffer, sizeof(buffer), stdin) == 0 ||
+	strcmp(buffer, "cont\n") == 0)
+      return 0;
+    if (luaL_loadbuffer(L, buffer, strlen(buffer), "=(debug command)") ||
+	lua_pcall(L, 0, 0, 0)) {
+      const char *s = lua_tostring(L, -1);
+      fputs(s ? s : "(error object is not a string)", stderr);
+      fputs("\n", stderr);
+    }
+    lua_settop(L, 0);  /* remove eventual returns */
+  }
+}
+
+/* ------------------------------------------------------------------------ */
+
+#define LEVELS1	12	/* size of the first part of the stack */
+#define LEVELS2	10	/* size of the second part of the stack */
+
+LJLIB_CF(debug_traceback)
+{
+  int arg;
+  lua_State *L1 = getthread(L, &arg);
+  const char *msg = lua_tostring(L, arg+1);
+  if (msg == NULL && L->top > L->base+arg)
+    L->top = L->base+arg+1;
+  else
+    luaL_traceback(L, L1, msg, lj_lib_optint(L, arg+2, (L == L1)));
+  return 1;
+}
+
+/* ------------------------------------------------------------------------ */
+
+#include "lj_libdef.h"
+
+LUALIB_API int luaopen_debug(lua_State *L)
+{
+  LJ_LIB_REG(L, LUA_DBLIBNAME, debug);
+  return 1;
+}
+